Video cassette recorder for detecting whether a video tape has been rewritten or its driving method

摘要

The present invention relates to a video cassette recorder, comprising: a recorder (1) for recording and outputting a video signal input upon application of a record control signal; A first control head 10 for reading and outputting a control pulse recorded on the video tape in the recording mode, and an erasing head 8 for erasing the video signal recorded on the video tape in response to the application of the erase signal in the recording mode. ), A video head 3 for recording an applied video signal on a video tape and reading and outputting the video signal recorded on the video tape; A second control head 9 for reading out and outputting the recorded control / bis signal; A deck (3) for driving the video tape at a predetermined speed upon application of a recording control signal and a reproduction control signal, and for rotating a head drum on which the video head (3) is mounted; A reproduction system 5 for reproducing and outputting a video signal applied from the video head 3 at the time of application of a reproduction control signal; A driving unit 7 for driving in accordance with the driving signal to indicate that a new video signal is recorded after the recorded video signal is erased; In the recording mode, the recording control signal is transmitted to the deck 3 and the recorder 1, and the control / bis signal having a different duty ratio is output to the second control head 9, according to the detection of the control signal from the first control head 10. An erasing signal is applied to the erasing head 8, and the reproduction control signal is transmitted to the deck 3 and the reproduction system 5 in the reproduction mode in accordance with the detection of the control / bis signal from the second control head 9. The microcomputer 2 which selectively outputs a drive signal to the drive part 7 is provided.